Galoitica: Journal of Mathematical Structures and Applications GJMSA 2834-5568 10.54216/GJSMA https://www.americaspg.com/journals/show/2285 2022 2022 Faculty of Administration and Economics, Economics department, University of Misan, Iraq Mudheher Abdul-Jabbar H. Albayati In this paper, the concept of reverse a-derivation on G-ring M, and some results concerning two reverse a-derivations on M that are related to classical result of E.Ponser are presented. These results shows that if M is a2-torsion free semiprime G-ring, d and g are non-zero reverse derivations of M, then dg are not a non-zero derivation. The new main results present and study notion of orthogonally reverse a-derivations  of M. 2023 2023 31 37 10.54216/GJMSA.090103 https://www.americaspg.com/articleinfo/33/show/2285